The present invention relates to a surface modification technique for a magnesium alloy material and, more particularly, to a magnesium alloy member consisting of or comprising a magnesium alloy material formed with a surface modified layer to achieve good adhesion (bonding/coating) properties.
In recent years, there are increasing applications of not only resin materials such as polyethylene resins and polypropylene resins but also light metal materials such as aluminum alloys and magnesium alloys for vehicle weight reductions. Various surface modification techniques, bonding techniques and coating techniques have been developed to produce composites of light metal materials or composites of light metal materials and other materials. One of the surface modification techniques is surface treatment of a metal material with a chromium-free acidic composition. For example, Patent Document 1 discloses a surface modification technique that forms a coating film on a metal material by surface treatment with an aqueous corrosion-resistant coating solution, and then, fixes the coating film to the metal surface by baking and drying without water washing.    Patent Document 1: Japanese Laid-Open Patent Publication No. 5-195244